An intelligent power module, i.e., an IPM, is a power driving product which combines a power electronic technology with an integrated circuit technology. The intelligent power module integrates a power switching device with a high voltage drive circuit, and is provided with a fault detection circuit for overvoltage, overcurrent, overheating and the like therein. The intelligent power module, on one hand, receives a control signal of MCU to drive a follow-up circuit to operate, and on the other hand, sends a status detection signal back to the MCU. Compared with a traditional discrete scheme, the intelligent power module wins a more and more bigger market due to its advantages such as high integration density, high reliability and the like, which is in particular suitable for a frequency converter of a drive motor and various inverter power sources, and is an ideal power electronic device for frequency conversion and speed governing, metallurgical machinery, electric traction, servo drive and inverter appliances.
Since the intelligent power module generally operates in a high temperature environment and a power component in the intelligent power module may emit a large amount of heat during its operation, resulting in a high junction temperature in the power device. Although a circuit base board may serve to dissipate heat, however due to existence of an insulating layer, an overall thermal resistance of the intelligent power module is high. A long-term high temperature environment may seriously reduce a service life of the intelligent power module, and may influence stability of properties of the intelligent power module. Particularly under an extreme case, it may lead to an incontrollable blast of the intelligent power module due to the overheating of an interior component during the operation, causing personal casualties and property damages.
The power devices of the intelligent power module may emit a large amount of heat during the operation, resulting in the high junction temperature of the power components. Though the circuit base board may serve to dissipate heat, however due to existence of the insulating layer, the overall thermal resistance of the intelligent power module is high. Moreover, due to heat conduction of the circuit base board, heat of the power components is transmitted to other components, allowing electrical parameters of the other components to generate a non-negligible temperature drift.
Employing a high thermal-conductive insulating layer and adding a radiator are a principal method to solve the heat-dissipation problem of the current intelligent power module. However, on one hand, cost of the high thermal-conductive insulating layer is very high, and on the other hand, the high thermal-conductive insulating layer has high hardness as using a large amount of doping, thereby increasing the manufacturing difficulty of the intelligent power module. If the radiator is added to the interior of the intelligent power module and the power components are mounted to a surface of the radiator, on one hand, the cost of raw material may be increased, and on the other hand, the processing difficulty of the intelligent power module may be increased. If the radiator is added to the exterior of the intelligent power module, the radiator needs to be mounted to a back face of the intelligent power module, on one hand, increasing the application cost and on the other hand, increasing the assembly difficulty, both of which create difficulties for application and promotion of the intelligent power module, thereby being bad for popularization of the intelligent power module in a civilian occasion.